1. Field of the Invention
The present invention relates to a reprojected image forming apparatus for forming a three-dimensional reprojected image from continuous two-dimensional tomographic images of, e.g., a material or a product obtained by a tomographic image forming apparatus such as an X-ray CT scanner, an NMR-CT system which utilizes a nuclear magnetic resonance phenomenon, and an ultrasonic tomographic apparatus and, more particularly, to a projected image forming apparatus for forming a pseudo three-dimensional reprojected image using a two-dimensional image processing means.
2. Description of the Related Art
Continuous tomographic images of a human body or an industrial product can be formed by a tomographic image forming apparatus such as an X-ray CT scanner, an NMR-CT system, and an ultrasonic tomographic apparatus. However, in order to three-dimensionally display these two-dimensional tomographic images (slice images), three-dimensional image processing must be performed.
Conventionally, in order to perform the three-dimensional image processing, continuous tomographic image data obtained by a tomographic image forming apparatus is stored in a magnetic disk apparatus which is an external memory apparatus. Then, a general computer sequentially reads out the tomographic image data from the magnetic disk apparatus and performs the three-dimensional image processing. A formed reprojected image is stored in the magnetic disk apparatus again.
However, the continuous tomographic images formed by the tomographic image forming apparatus require an enormous memory capacity, and the processing is performed using the general computer while the continuous tomographic images are sequentially read out from the magnetic disk apparatus. Therefore, even if the computer has a high processing speed, the three-dimensional processing requires a considerably long time period. In addition, since the general computer is used, the overall system cannot be made compact.